"Eight hours of sleep makes a big difference for me, and I try hard to make that a priority," he tells Thrive Global. "For me, that's the needed amount to feel energized and excited."

Adequate rest not only leaves Bezos invigorated for the day to come but allows him to continuously make sharp, thoughtful choices without suffering from decision fatigue. That's what can happen when choices become harder as a day goes on and you deplete your finite store of energy.

"Mostly, as any of us go through our lives, we don't need to maximize the number of decisions we make per day," Bezos explains. "Making a small number of key decisions well is more important than making a large number of decisions. If you shortchange your sleep, you might get a couple of extra 'productive' hours, but that productivity might be an illusion."

Your work can suffer when you're tired. "When you're talking about decisions and interactions, quality is usually more important than quantity," he says.

Science is on Bezos' side. Researchers for the Harvard Business Review found a link between adequate sleep and effective leadership, pointing out that all four of the most common leadership behaviors associated with high-performing teams were hindered by a lack of sleep.

Matthew Staver | Bloomberg | Getty Images

Jeff Bezos, chief executive officer of Amazon.com

One study found that after being awake for more than 17 to 19 hours, participants' performance slipped to that of someone with a blood alcohol content of 0.05 percent. For reference, in many U.S. states the legal BAC is 0.08 percent.